I've always heard it as fuck-you money. Meaning you can afford to say, "fuck-you" to anyone you want (boss, your competition, a cop, etc...) and not have to worry about paying your bills tomorrow.
On an unrelated note, I think people gives Taleb too much credit. Sure, he's a fantastic author and the points he bring up are interesting and noteworthy but he isn't a good trader. I just don't understand why retail investors like to think that Taleb is in the same league as Ken Griffith and worship Fooled by Randomness/Black Swan as a trading bible. It's not. If you try to apply his principles on the market, you'll bleed to death slowly and maybe once a while during a Black Swan event, you get a blood transfusion but in the long run, you'll die. There's a reason why those out-of-the-money options are cheap. It's called probability.
